Supporting object recognition has become one of basic features in the operation interface of smart glasses. However, the portable device, e.g. the smart glasses, supporting the gesture recognition faces some problems. To accurately recognize individual data with three dimensions (e.g. translation (shifting), scaling, and rotation) may involve a great deal of data to be processed and spend a lot of time. When the gesture recognition is applied in the image capturing or the video recording, the user's hand may be captured easily and presented in images captured by a user. Since each one has his hand gestures, the user may not be satisfied with only one common gesture setting.